Abstract:
Iranian researchers synthesized a silica-coated iron oxide nanocomposite which can be used in the diagnosis and treatment of ailments inside the body.

Silica-Coated Iron Oxide Nanocomposite Produced for Medical Uses

Iran | Posted on August 15th, 2010

These nanoshell particles are a special type of nanocomposites that consist of magnetic iron oxide nanoparticles as the main core, and a thin shell of diamagnetic silica that has a high potential to be applied in magnetic resonance imaging and drug delivery.

"A solution was made of ferric chloride 6-hydrage, ferrous chloride 4-hydrate, hydrochloric acid, and twice-distilled water," Lida Qazanfari, one of the researchers, told the news service of Iran Nanotechnology Initiative Council, elaborating on the process of the research.

"Sodium hydroxide solution has also been made as the alkaline solution. By adding NaOH solution to the mixture of FeCl3 and FeCl2 salts, a suspension of magnetite (Fe3O4) was obtained through a coprecipitation method. In order to prevent the agglomeration of the nanoparticles and to increase their stability in the polar environment of water, tri-sodium citrate (TSC) solution was added to coat the surface of the nanoparticles. A black solid powder was obtained by putting the sample in a freeze dryer," she added.

"A magnetic solution was prepared from the powder in order to coat the surface of the particles with silica. At this stage and according to Stober method (with a little modification), the coating of the surface of magnetite nanoparticles stabilized with a coating of silica was carried out through hydrolysis and compression of tetra-ethyl orthosilicate (TEOS) in an ethanol/water based mixture at room temperature," Qazanfari continued.

The synthesized composite nanoparticles have single scattering properties and quick magnetic response in the optimum conditions. Those characteristics are mandatory for the application of the nanoparticles in medical engineering.